ci: update upload-artifacts as it was failing builds

Author: isXander

.github/workflows/gradle.yml

@@ -47,7 +47,7 @@ jobs:
         run: chmod +x gradlew
       - name: Build with Gradle
         run: ./gradlew build --no-daemon
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: debugify-artifacts
           path: build/libs/*.jar